Carla Jaeger, since a very young age, can notice the way her mom stiffens when there is a knock in the door.
They may know who is coming; the person may yell their name before she opens the door, but every time she looks at Carla, a harsh look like saying "run if I tell you to".
Not many people come to their house; they live in a place far away from other people, from The Walls, as her parents call them.
Carla doesn't really understand why her mother, her kind, gentle, happy mother looks at her like that, so worried, so serious, so desperate.
She doesn't understand why, once her brother is born, her mother puts the baby on her arms before she goes to open the door.
It takes a lot of time for her to know why her mother holds a knife when she goes to get the door, why her dad laughs when he walks in, and kisses her face and whispers things, and why she cries in the night with him.
It takes a while for her to know why her mother tries to shield her brother, her black haired, black eyed brother against anyone she doesn't trust, and why she doesn't do that so often with brown haired, green eyed Carla.
It takes a while for her to learn about races, and Orientals, and even longer for her to know about the bad people who want them.
She learns it the bad way, when it's too late for her mother and she's running with a toddler in her arms, screaming for Annie to go back and save her mother, screaming for Armin to take her brother and run.
When she screams for her father come back soon, and he doesn't until it's too late.